How to Measure for Fireplace Doors

First determine if your fireplace is a factory built
prefabricated fireplace (zero-clearance) or a masonry type fireplace. The
easy way to tell is to look at the chimney. If you have an all masonry chimney
(brick & mortar with clay tile liners) then you have what is considered
a masonry fireplace. If your chimney is a metal chimney pipe (usually with
a round chimney cap) then you have a pre-fabricated fireplace.

When installing fireplace
glass doors, correctly measuring your fireplace is crucial. We have
put together a guide to help you accurately measure your masonry or prefab
or zero clearance fireplace.

Measuring Masonry Fireplaces

Be sure to take all measurements to the nearest 1/16"
using a steel tape measure. For complex custom applications, a photograph of
the fireplace will be very helpful. Be sure to look for projecting bricks, rotary
damper handles, or any other issues that may cause a problem when mounting your
fireplace door. Click here for examples of unusual or custom applications that
require consideration when ordering a fireplace door. For questions please contact
one of our fireplace door experts Toll Free at 866-Northline ( 866-667-8454
).

There are two types of fit, Overlap Fit and Inside Fit. The
overlap fit is when the fireplace door is larger than the fireplace opening
and the door will overlap the brick, marble, etc. An inside fit is when the
fireplace door fits inside the fireplace opening and will be flush with the
brick, marble, etc. The most common is the overlap fit but if you have rough
field stone or bricks protruding, then the inside fit may be more appropriate.
The inside fit requires more precise measuring and is used with custom enclosures
only. All stock doors utilize an overlap fit. In general, you will usually obtain
a better fit and easier installation when you use the overlap fit, when possible.

Overlap Fit

Measure the width of the opening at the top and again at
the bottom. We need the minimum and maximum width (A). It might be helpful to
print this page and use Figure 1 for all your measurements.

Next, measure the height of the opening from the hearth (where
the enclosure will sit) to the top of the fireplace opening. If there is no
hearth extension or you have a raised firebox, you will need to overlap the
bottom of the opening (picture frame mount). To aid in this installation, you
will need to use a suspension bar, click here for an illustration. The suspension
bar drops down 5/8", therefore adding 5/8" to the effective opening.

Inside Fit

Measure the width of the opening at the top and again at
the bottom. We need the minimum width. See figure 1. Next, measure the height
of the opening from the hearth (where the enclosure will sit) to both the bottom
of the lintel bar, and to the bottom of the finishing material (brick, marble,
etc.) See figure 2.

Notes on Inside Fit Enclosures:

Width - For example, if the top width
is 42" and the bottom width is 41 1/2", we will make the enclosure
41 1/4" wide allowing 1/8" clearance tolerance on each side. This
means that at the top, there would be a 3/8" gap (in this example)
between the side panel and the fireplace opening on each side. Generally
the clearance gaps can be filled from the backside of the frame using high
temperature RTV silicone. If the gaps become excessive (as in a stone fireplace),
it may be necessary to mortar in the enclosure. Factory tolerance of a fireplace
door is generally + or - 1/32".

Height - If you are planning on installing
the enclosure under the brick, the face of the lintel bar must be back far
enough from the face of the fireplace for the door to fit, otherwise the
lintel will keep the enclosure from going in all the way flush. The distance
from the face of the fireplace to the face of the lintel bar must be indicated
in the area provided on the custom order form before we can begin processing
your order. See figure 2.

Measuring Zero-Clearance Fireplaces

Determine the manufacturer and model number of the fireplace.
This information is usually located high on the inside wall of the fireplace
above the refractory panels or behind the mesh curtain on the inset return.
Once this information is obtained, check to see if the fireplace door you are
looking at has a replacement door for that model. If the fireplace manufacturer
and model are not listed please contact one of our fireplace door experts Toll
Free at 866-Northline ( 866-667-8454 ).

Custom Z-Door Measuring: Measure the width
and height of the steel opening where the enclosure will fit, see figure 1 above.
Do not measure the finish material in front of the fireplace; brick, stone,
marble, etc. You may need to remove the mesh track to install the Z-Door, so
measure accordingly. It is very important not to modify or remove any other
component of the fireplace. Determine if Air Studs or an Air Draft Bar should
be used. The Air Stud will not add any thickness to the enclosure, and is used
when there is an "ash lip" in the refractory or there is not enough
inset depth. The Air Draft Bar is used more with "masonry appearance"
type zero clearance fireplaces. The Air Draft Bar will add 5/8" thickness
to the enclosure, making the enclosure extend forward from the fireplace. Air
Stud Example: If the inset is 1", and the thickness of the enclosure is
1 1/8", then the enclosure will extend forward from the face of the fireplace
1/8". See figure 3.

The enclosure will be manufactured based on the
fireplace opening dimensions you provide less the cooling air intakes.

Please be sure to measure accurately. All custom fireplace doors are made
to your specifications and are non-returnable unless defective. If you have
any questions please do not hesitate to call Toll Free at 866-Northline ( 866-667-8454
).